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We describe the current status of high-precision ab initio calculations of the spectra of molecular hydrogen ions (H2+ and HD+) and of two experiments for vibrational spectroscopy. The perspectives for a comparison between theory and experiment at a level of 1 part in 109 are considered. [ABSTRACT FROM AUTHOR]

We discuss new values of nuclear magnetic dipole moments, obtained from accurate absolute shielding constants and gas-phase NMR data, for a series of nuclei. The generally accepted previous values of magnetic moments were for many isotopes derived from NMR spectra. However, in the procedure applied to determine the moments of bare nuclei the effects of the molecular electronic structure have been often described in a very approximate manner. Accurate absolute shielding scales can be presently established analysing gas-phase NMR spectra and shielding constants determined by ab initio methods of quantum chemistry. We present a systematic analysis of the nuclear magnetic moments, based on the relation between these moments, the resonance frequencies and the shielding constants. With the new values of nuclear magnetic dipole moments the relations between the NMR parameters of different nuclei are fulfilled in a consistent manner, whereas using the literature values leads to significant errors. [ABSTRACT FROM AUTHOR]

A radiofrequency quadrupole antiproton decelerator, a femtosecond optical frequency comb and continuous-wave pulse-amplified laser were used to measure 12 transition frequencies of antiprotonic helium (metastable three-body neutral atom consisting of an electron, an antiproton and a helium nucleus) to fractional precisions of (9-16)× 10-9. Comparisons with three-body QED calculations yielded an antiproton-to-electron mass ratio of mp /me =1836.152674(5). The physics of antiprotonic helium atom spectroscopy and the method of mp/me determination are presented, and future prospects are discussed. [ABSTRACT FROM AUTHOR]

Strong-interaction shift ε1s and broadening Γ1s in the pionic hydrogen atom are determined from the energies and line widths of X-ray transitions to the 1s ground state. They are directly connected to the π N; scattering lengths which are related to the π N; coupling constant and the π N; sigma term being a measure of chiral symmetry breaking. Therefore, the measurement of the pion-nucleon s-wave scattering lengths constitutes a high-precision test of the methods of chiral perturbation theory (χPT), which is the low-energy approach of QCD. Additional constraints for the π N; scattering lengths are obtained from the measurement of the ground-state shift in pionic deuterium. The hadronic width is linked to s-wave pion production in nucleon-nucleon collisions. A new experiment, set up at the Paul Scherrer Institut (PSI), has finished taking data recently and will allow the determination of the scattering lengths at the few per cent level. [ABSTRACT FROM AUTHOR]

In this review we address the topic of X-ray spectroscopic investigations of the ground-state transitions in the heaviest one-electron systems by using the intense beams of cooled heavy ions provided by the Experimental Storage Ring (ESR) at GSI Darmstadt. Such experiments on high-Z ions open up unique possibilities for the investigation of the quantum electrodynamical (QED) effects in the nonperturbative domain of extremely strong electromagnetic fields. Particular emphasis is given to the developments as well as to the current progress for the future experiments aiming for the sensitive tests of the higher-order bound-state QED effects. These include novel high-resolution detection systems: crystal spectrometers in combination with position-sensitive solid-state detectors and bolometers. [ABSTRACT FROM AUTHOR]

Lithium has a number of properties that make it useful for both experimental and theoretical study. Precise spectroscopic measurements of optical transitions in both Li+ and neutral Li are reviewed. Experiments have yielded hyperfine and fine structure splittings that test QED as well as isotope shifts that determine the relative nuclear charge radius between isotopes to an accuracy of 2 X 10−17 m. Experimental and theoretical results agree very well for Li+ and a measurement of the fine structure of the 1s2p 3P0,1,2 levels is of interest to determine the fine structure constant. For neutral lithium, additional theoretical work is needed to match the experimental accuracy for the 2P fine structure splitting. [ABSTRACT FROM AUTHOR]

The form factors of proton and neutron provide a natural and direct insight into their internal structure. They were a main research goal in the nuclear physics program of the Universitát Mainz, which led to some of the most precise measurements to date. This article gives an overview, starting from the very first experiments at the now obsolete linear accelerator and ending at the exhaustive experiments currently underway at the Mainz Microtron (MAMI) facilities. [ABSTRACT FROM AUTHOR]

We summarize various analyses of the world data on elastic electron scattering for the determination of the most precise rms-radii of light nuclei. We also present the Zemach moments needed for the interpretation of atomic hyperfine structure and µ-X-ray experiments. [ABSTRACT FROM AUTHOR]

The CODATA recommended values of the fundamental constants are widely applied in particle, nuclear and atomic physics. They are a result of a complicated evaluation (adjustment) of numerous correlated data of different natures. Their application is often rather mechanical and as a result is not free of various confusions which are discussed in this note. [ABSTRACT FROM AUTHOR]

The muon anomalous magnetic moment is one of the most precisely measured quantities in particle physics. Recent high-precision measurements (0.5 ppm) at Brookhaven reveal a "discrepancy" by three standard deviations from the electroweak Standard Model which could be a hint for an unknown contribution from physics beyond the Standard Model. This triggered numerous speculations about the possible origin of the "missing piece". The remarkable 15-fold improvement of the previous CERN experiment actually animated a multitude of new theoretical efforts which led to a substantial improvement of the prediction of aµ. The dominating uncertainty of the prediction, caused by strong interaction effects, could be reduced substantially, due to new hadronic cross-section measurements in electron-positron annihilation at low energies. After an introduction and a brief description of the principle of the experiment, I review the status of the theoretical prediction and discuss the role of the hadronic vacuum polarization effects and the hadronic lightby-light scattering contribution. Prospects for the future will be briefly discussed. As, in electroweak precision physics, the muon g - 2 shows the largest established deviation between theory and experiment at present, it will remain one of the hot topics in future also. [ABSTRACT FROM AUTHOR]

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[This address was presented by Pierre-Gilles de Gennes as the Nishina Memorial Lecture at the University of Tokyo, on April 3, 1998.] We present here some general features of granular materials, of their importance, and of the conceptual difficulties which they exhibit. For static problems, we insist on the difference between textures, which represent frozen correlations between grains, and stress tensors. We argue that in systems like heaps and silos, texture is present, but the main features of the stress distribution do not depend on it, and a description using an isotropic medium is a good starting point. We also discuss avalanche flows, using a modified version of the equations of Bouchaud et al, which might be valid for thick avalanches. [ABSTRACT FROM AUTHOR]

[This address was presented by JamesW. Cronin as the NishinaMemorial Lecture at the University of Tokyo, and at Yukawa Institute for Theoretical Physics in September, 1993.] The discovery of CP violation was a complete surprise to the experimentalists that found it as well as to the physics community at large. This small effect means that the symmetry means that the symmetry between the behavior of matter and antimatter is not exact. The experiment that made the discovery was not motivated by the idea that such a violation might exist. I will describe in some detail how it came to be performed in the context of of the fast moving pace of particle physics in 1963. I will review how we actually did the experiment using extracts from personal notebooks. I will discuss some difficulties we had with the apparatus and the anxiety some of us had to be sure we were correct. Such considerations are rarely revealed in a formal publication but are the realities of doing science. I will then discuss the aftermath of the experiment and the great efforts that continue to this day to understand the origin of the CP violation, which remains a mystery. The search for the origin of CP violation motivates many of the proposals for new particle facilities. [ABSTRACT FROM AUTHOR]

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This address was presented by Leon Van Hove as the Nishina Memorial Lecture at the University of Tokyo, on April 11, 1990. [ABSTRACT FROM AUTHOR]

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This address was presented by Kai Siegbahn as the Nishina Memorial Lecture at the University of Tokyo, on April 4, 1988. [ABSTRACT FROM AUTHOR]

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This address was presented by Chien-ShiungWu as the Nishina Memorial Lecture at the University of Tokyo, March 31, 1983 [ABSTRACT FROM AUTHOR]

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This address was presented by Ryogo Kubo as the Nishina Centennial Symposium at the Japan Medical Association(Tokyo), December 5, 1990. [ABSTRACT FROM AUTHOR]

Copyright of Nishina Memorial Lectures is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)